I have a number of DA/SA (also called TDA for traditional double action) pistols in 9mm so maybe I can offer some suggestions.
Beretta- look at the 92 series. The military has been using it for twenty years and it is a reasonably priced, reliable pistol.
CZ- look at the CZ-75 PCR. It is an aluminum framed pistol with a decocker. Most of the CZ pistols are excellent.
Sig- look at the 226, 228 and 229. The 226 is the full size, the others a mid-size. Almost any Sig you get is great right out of the box.
HK- I have one of the USP-compact pistols (but in .45 caliber). Many people have difficulty finding aftermarket parts and customer service can be terrible. New magazines are expensive, about $50 apiece. Generally they are more expensive than a comparable quality pistol as you are paying for the name brand.
And don't forget the used market. There are a number of high quality 9mm's with very little use for sale at great prices. Take a look at [url=http://www.summitgunbroker.com.[/url]. In particular look at used SW pistols like the 5906, 5903, 6906.
Good luck- oldandslow